Various tumor related diseases inflict man and other mammals and, as these conditions are often fatal, the prevention, control of growth and regression of tumors in mammals has been receiving widespread attention by the medical profession and pharmaceutical industry. The term tumor refers to abnormal masses of new tissue growth which is discordant with the economy of the tissue of origin or the host's body as a whole.
Tumors inflict mammals and man with a variety of disorders and conditions including various forms of cancer and resultant cancerous cachexia, which term refers to the symptomatic discomfort that accompanies the infliction of a mammal with a tumor. Such symptoms include weakened condition of the inflicted mammal as evidenced by weight loss, etc. The seriousness of cancer is well known since cancer is a major cause of death in man.
Considerable research and resources have been devoted to oncology and antitumor measures including chemotherapy. While various antitumor agents and methods have been developed which aid in inhibiting tumors, additional methods and chemical agents are needed.
Viral diseases also inflict man, plants, insects and animals. The prevention and control of viral diseases has important health and economic implications.
Viral diseases contribute to inflictions in humans including common colds, herpes, acquired immune deficiency syndrome and cancer so the importance of their control is obvious. Also important is the control of viral diseases in animals for economic and other reasons, e.g., the ability of such animals to become virus reservovirs or carriers which facilitate the spreading of viral diseases to humans. Viral plant diseases have been known to have a disruptive effect on the cultivation of fruit trees, tobacco and various vegetables. Insect viral diseases are also of interest because of the insects' ability to transfer viral diseases to humans.
The prevention and control of viral diseases is thus of prime importance to man and considerable research has been devoted to antiviral measures. Certain methods and chemical compositions have been developed which aid in inhibiting, controlling or destroying viruses, but additional methods and antiviral compositions are needed.
A potential source for biologically active compounds of great diversity is marine plants and animals. In fact, marine sponges have proved to be a productive source for such compounds. Some such molecules derived from sponges are described in Scheuer, P. J., Marine Natural Products, Chemical and Biological Perspectives; Academic Press; New York, 1978-1983; Vol. I-V; Kato et al., Tetrahedron Letters, Vol. 26, Pg. 3483-6 (1985); and Capon and Macleod, Tetrahedron, Vol. 41, Pg. 3391-3404 (1985). The entire disclosures of these references are hereby incorporated herein by reference.
Another naturally derived composition of interest is pederin. Pederin is isolated from insects of the Paederus genus. Pederin shows antimitotic activity as described in British Pat. Nos. 1,078,049 (1967) and 932,875 (1963).
It has now been found that certain compounds derived from extracts of marine sponge of the genus Mycale, family Mycalidae, and order Poecilosclerida, possess useful biological activity.